$ B = \left[\begin{array}{rr}1 & 8 \\ 7 & 2 \\ 1 & 3\end{array}\right]$ What is $ B^{T}$ ?
To find the transpose, swap the rows and columns. $ B^{T}$ = $\left[\begin{array}{rrr}1 & 7 & 1 \\ 8 & 2 & 3\end{array}\right]$